A fuel emitter and an EUV radiation source generating device containing the same

Abstract

The present invention discloses a fuel emitter and an EUV radiation source generating device containing the same. The EUV radiation source generating device includes a collector, a fuel emitter, a monitoring system, a laser, and a waste receiving pipeline. In the present invention, the fuel emitter transports fuel to the break of two wires through a pump to achieve a circuit connection. Under the action of a strong magnetic field, the fuel droplets are subjected to the Ampere force and accelerate along the nozzle wall to be emitted. Relevant data on the flight trajectory of the fuel droplets is obtained through the monitoring system. The laser obtains relevant data before the fuel droplets reach the plasma formation region, determines the timing of the excitation laser pulse through data analysis, and then realizes two consecutive precise strikes to excite extreme ultraviolet light photons. The formed point radiation source is reflected out of the emission port at the top of the collector by an ellipsoidal mirror, thereby realizing the preparation and collection of the EUV radiation source.

Description

Technical Field

[0001] The present invention belongs to the technical field of lithography machine auxiliary devices, and particularly relates to a fuel emitter for a lithography machine and an EUV radiation source generating device containing the same. Background Art

[0002] Extreme Ultra-violet lithography, often referred to as EUV lithography, is a lithography technology that uses extreme ultraviolet light with a wavelength of 10 - 14 nm as a radiation source. The main difficulties in preparing an EUV lithography machine lie in the preparation and collection of the EUV radiation source. Currently, the main method for preparing and collecting the EUV radiation source is to emit micron-sized metal tin droplets by a fuel emitter, and then continuously and accurately strike the metal tin droplets with a high-power carbon dioxide laser emitter to excite EUV extreme ultraviolet light photons. Then, through multiple reflections, the propagation direction of light is controlled and other wavelengths of light are absorbed to form an EUV radiation beam that can be used for lithography of the lithography machine, so as to realize the preparation and collection of EUV extreme ultraviolet light.

[0003] Currently, in the patents of fuel emitters or droplet generators for EUV lithography machines that are publicly available, such as the patent with the patent number 202011163837.X and the patent name of an EUV light source target droplet generating device and method, the method described therein is to pressurize the liquid material in the cavity with an inert gas to form a jet; apply a perturbation to the jet so that the jet forms a droplet train under the Rayleigh instability principle; make the droplet train pass through a charged orifice plate so that the droplets are charged; make the charged droplet train pass through a charged deflection electrode plate, and the charged droplet train is divided into main droplets and satellite droplets under the action of the electric field force; use a laser to bombard the satellite droplets, and use a liquid recovery component to recover the main droplets. The satellite droplets prepared by the method described in this invention have problems such as random size, random flow path, unfixed intensity of the formed radiation source, and unfixed formation position of the point radiation source, and still cannot meet the requirements of the fuel emitter for the EUV lithography machine.

[0004] In summary, the deficiencies of the prior art are as follows:

[0005] 1. It is difficult to prepare a sufficient number of fuel droplets with appropriate volume and relatively fixed size per unit time;

[0006] 2. There may be a phenomenon of mutual fusion between droplets;

[0007] 3. It is impossible to continuously emit fuel droplets along a fixed route and make the formation position of the subsequent point radiation source relatively fixed, which is convenient for subsequent collection. Summary of the Invention

[0008] The purpose of the present invention is to provide a fuel emitter for a lithography machine and an EUV radiation source generating device containing the same to solve the problems of the prior art.

[0009] The present invention is achieved through the following technical solutions: A fuel emitter, characterized in that:

[0010] It includes a nozzle, on the inner wall of the nozzle, two groups of conductors are axially arranged, and on the outer wall of the nozzle, two wires are symmetrically arranged, and the two wires are respectively electrically connected to the two groups of conductors;

[0011] It further includes a magnetic field generator, which is arranged outside the nozzle and the magnetic field direction is perpendicular to the nozzle and the wires;

[0012] An outer shell is arranged outside the nozzle and the magnetic field generator, and the outermost end part of the nozzle protrudes outside the outer shell;

[0013] It further includes a fuel pump, the inlet end of the fuel pump is connected to the fuel storage tank through an insulating pipe, and the outlet end of the fuel pump is connected to the inlet of the nozzle through an insulating pipe.

[0014] Further: A protective pipe is arranged outside the wire, and the wire and the protective pipe are arranged along the radial direction of the nozzle.

[0015] Further: The inner wall of the outer shell is provided with a magnetic shielding layer, and its material is soft iron, silicon steel, permalloy or soft ferrite.

[0016] Further: The magnetic field generator and the fuel pump are provided with an electric control switch, which is electrically connected to the wire.

[0017] The present invention further includes an EUV radiation source generating device, characterized in that:

[0018] It includes the fuel emitter as described above;

[0019] It further includes a collector, a monitoring system, a laser, and a waste receiving pipeline;

[0020] The collector includes a conical shell, a light source outlet is arranged at the upper part of the shell, an ellipsoidal reflector is arranged at the lower part of the shell, and a laser emission port matching with the laser is arranged at the bottom of the ellipsoidal reflector;

[0021] The fuel emitter and the waste receiving pipeline are correspondingly arranged on both sides of the shell;

[0022] The monitoring system includes an auxiliary laser generator and a sensor cooperating with it, and the two are correspondingly arranged on the shell, and the connection line intersects with the running path of the fuel.

[0023] Further: The auxiliary laser generator is provided with an electric control switch, which is electrically connected to the wire of the fuel emitter.

[0024] Further: The laser is arranged at the laser emission port of the ellipsoidal reflector and is electrically connected to the sensor through a wire.

[0025] Further: The collector is provided with a coating, which is alternately composed of silicon material and molybdenum material. The collector is inclined towards the waste receiving pipeline side and is provided with a support structure.

[0026] Further: The fuel is metallic tin.

[0027] Further: The insulating tube and the nozzle are both made of boron nitride, and the inner walls of the storage tank and the pump are both provided with boron nitride insulating layers.

[0028] Further: The conductor is silver or copper.

[0029] Further: The outer wall of the outer shell is provided with a coating, which is alternately composed of silicon material and molybdenum material, and the inner wall is provided with a magnetic shielding layer, and its material is soft iron, silicon steel, permalloy or soft ferrite.

[0030] Further: A wire is provided in the waste receiving pipeline for discharging the charges of the waste or the unexcited fuel.

[0031] The advantages of the present invention are:

[0032] 1. By opening or closing the pump through the electric control switch on the pump, the continuous preparation of fuel droplets is realized. When the time intervals for opening or closing the pump each time are the same, the sizes of the prepared fuel droplets can be consistent; the volume of each fuel droplet is controlled by the volume of the gap at the wire break and the performance of the pump; when the opening and closing interval of the pump is controlled within 10 -5 s, the preparation of 50,000 fuel droplets per second can be realized;

[0033] 2. The fuel droplets carry the same charge in the nozzle and repel each other, which is beneficial to avoiding the mutual fusion of the fuel droplets. In addition, the fuel droplets move at an accelerated speed in the nozzle, and the running speed of the fuel droplets generated first is always faster than that of the fuel droplets generated later, so that the fuel droplets generated later cannot catch up with the fuel droplets generated first, thus avoiding the fusion of the fuel droplets;

[0034] 3. When the fuel droplet moves inside the nozzle, the acting forces it experiences are relatively simple and fixed, namely gravity, supporting force, frictional force, and Ampere force. Among them, the direction of the gravity is always downward, the direction of the supporting force is always perpendicular to the nozzle wall, the Ampere force is in the same direction as the moving direction of the fuel droplet, and the frictional force is in the opposite direction to the moving direction of the fuel droplet. By controlling parameters such as the volume of the fuel droplet, the current intensity, and the magnetic induction intensity, the magnitudes of the acting forces can be controlled, thereby effectively controlling the moving speed of the fuel droplet inside the nozzle. Since the outermost end of the nozzle protrudes outside the housing, a magnetic shielding layer is provided on the inner wall of the housing. At the outermost end of the nozzle, there is no magnetic field intensity, and the fuel droplet will not be affected by the Lorentz force after leaving the nozzle to change its flight trajectory. In summary, both the flight trajectory and the moving speed of the fuel droplet after leaving the nozzle are controllable, and the present invention achieves the effect of continuously emitting fuel droplets along a straight or nearly straight fixed path.

[0035] In summary, the fuel emitter described in the present invention meets the requirements of the fuel emitter for preparing an EUV radiation source, thereby making the formed radiation intensity relatively stable and the formation position of the EUV radiation source relatively fixed, facilitating the subsequent collection of EUV radiation.

[0036] In addition, for the EUV radiation source generating device described in the present invention, the flight trajectory data of the fuel droplet is obtained through the monitoring system, which helps the laser obtain relevant data before the fuel droplet reaches the plasma formation region. Through data analysis, the fuel droplet can be accurately hit twice continuously, thereby preparing an EUV radiation source. Since the formation position of the EUV radiation source is relatively fixed, the formed radiation source can be reflected out of the light source outlet by an ellipsoidal mirror, and the EUV radiation source is collected into a beam of radiation. Brief Description of the Drawings

[0037] Figure 1 is the overall structural schematic diagram of the fuel emitter;

[0038] Figure 2 is Figure 1 the front view of

[0039] Figure 3 is the structural schematic diagram of the EUV radiation source generating device;

[0040] Figure 4 is the structural schematic diagram of the control circuit;

[0041] Figure 5 is the schematic diagram of the working principle of the electric control switch of the fuel pump;

[0042] Explanation of the reference numerals in the figures: 1 is the collector, 2 is the fuel emitter, 3 is the monitoring system, 4 is the laser, and 5 is the waste receiving pipeline;

[0043] 11 is the housing, 12 is the light source outlet, 13 is the ellipsoidal mirror, and 14 is the laser emission port;

[0044] 21 is the nozzle, 22 is the through hole, 23 is the conductor, 24 is the wire, 25 is the wire protection tube, 26 is the magnetic field generator, 27 is the outer shell, 28 is the fuel pump, 29 is the fuel storage tank, 210 is the insulating tube, 211 is the power supply, and 212 is the electrical signal amplifier;

[0045] 31 is the auxiliary laser generator, and 32 is the sensor;

[0046] 61 is the electric control switch of the magnetic field generator;

[0047] 621, 622, and 623 are the electric control switches of the fuel pump;

[0048] 63 is the electric control switch of the auxiliary laser;

[0049] In the electrical signal amplifier, 2121 is an NPN type triode, and 2122 is the power supply;

[0050] R1 and R2 are resistors. Embodiment

[0051] Reference appendix Figures 1-5 The present invention provides a fuel emitter 2, which includes a nozzle 21. The nozzle is a cylindrical insulator with a through hole 22 provided at the center. Two sets of conductors 23 are axially provided on the inner wall of the nozzle through hole. Two wires 24 are symmetrically provided on the outer wall of the nozzle, and the two wires are respectively electrically connected to the two sets of conductors; a wire protection tube 25 is provided outside the wires; it further includes a magnetic field generator 26. The magnetic field generator is provided outside the nozzle and the magnetic field direction is perpendicular to the plane where the nozzle and the wires are located; an outer shell 27 is provided outside the nozzle, the magnetic field generator, the wires, etc. The front end of the nozzle extends out of the outer shell. The outer shell is made of a magnetic shielding material, which can shield the magnetic field so that the magnetic field only acts on the inner side of the shell; it further includes a fuel pump 28. The feed end of the fuel pump is connected to the fuel storage tank 29 through an insulating tube 210, and the discharge end of the fuel pump is connected to the inlet of the nozzle through an insulating tube. The fuel pump pumps fuel into the nozzle. The size of the fuel droplets entering the nozzle is adapted to the inner diameter of the nozzle, can fill part of the pipe diameter, and connect the two sets of conductors to connect the two wires. At the same time, the circuit is connected to generate an electric current in the fuel droplets, so that they are affected by the magnetic force and accelerated.

[0052] Preferably, the nozzle, the wire, and the power supply form a control circuit. The nozzle is equivalent to the break point of the wire. When there are droplets inside it, the circuit is connected. When there are no droplets, the circuit is disconnected, thus forming a control terminal. Further, for the stability of the circuit and the strength of the signal, a signal amplifier is also connected to the circuit, and a resistor is provided. One or more electronic control switches are provided on the control circuit. The multiple electronic control switches are connected in parallel and arranged in the control circuit. The electronic control switch is used to control the on / off of the branch it is in, and further realize the linkage between the control circuit and each branch. Each branch includes a monitoring system, a magnetic field generator, a fuel pump control branch, etc.

[0053] Preferably, the wire protection tubes are symmetrically arranged along the radial direction of the nozzle. The two wire protection tubes are in a straight line and perpendicular to the nozzle.

[0054] Preferably, a magnetic shielding layer is provided on the inner wall of the outer shell, and its material is soft iron, silicon steel, permalloy or soft ferrite.

[0055] Preferably, the electric signal amplifier is used to amplify the tiny current signal of the control circuit where the wire is located, forming an amplification circuit. It is provided with an independent auxiliary power supply 2122 and an NPN-type triode 2121 for amplifying the electric signal, facilitating the transmission of the electric signal to a designated position.

[0056] The present invention also discloses an EUV radiation source generating device, which includes the aforementioned fuel emitter 2; it also includes a collector 1, a monitoring system 3, a laser 4, and a waste receiving pipeline 5; the fuel emitter 2 can emit fuel to the excitation point position inside the collector; the collector 1 can collect the generated radiation source; the monitoring system 3 can monitor the dynamics of the fuel droplets to help the laser 4 determine the excitation timing. The laser 4 generates laser at the corresponding excitation point position according to the feedback of the monitoring system, exciting the fuel droplets passing through the excitation point position; the waste receiving pipeline 5 recovers the residual waste and unexcited droplets after excitation.

[0057] Among them, the collector includes a conical housing 11. A light source outlet 12 is provided at the upper part of the housing, and an ellipsoidal reflector 13 is provided at the lower part of the housing. A laser emission port 14 cooperating with the laser is provided at the bottom of the ellipsoidal reflector 13; the ellipsoidal reflector 13 can reflect the radiation source generated at the excitation point to the light source outlet. The nozzle of the fuel emitter and the waste receiving pipeline 5 are correspondingly arranged on both sides of the housing. The monitoring system 3 includes an auxiliary laser generator 31 and a sensor 32 cooperating with it. The sensor is an optical sensor that receives the laser generated by the laser generator. The two are correspondingly arranged on the housing, and the connection line intersects with the running path of the fuel. That is, during the running process of the fuel, it will block the sensor from receiving the laser, and the sensor will generate a corresponding electric signal and transmit it to the corresponding component, thereby judging the position of the droplet, etc.

[0058] Preferably, the collector is provided with a coating, which is composed of overlapping silicon material and molybdenum material, with a total of 40 layers, which can effectively prevent radiation from spilling out. Figure 3 As shown, the collector is inclined toward one side of the waste receiving pipeline and is provided with a supporting structure, which can be supported by connecting with other components that have been supported.

[0059] Preferably, the fuel is metallic tin, and a heating device is provided outside the fuel storage tank to heat the metallic tin to a liquid state when the system is running.

[0060] Preferably, the insulating tube and the nozzle are both made of boron nitride, and the inner walls of the fuel storage tank and the fuel pump are both provided with an insulating layer made of boron nitride.

[0061] Preferably: the outer diameter of the insulating tube is 20 mm, the inner diameter of the end connected to the nozzle and the fuel pump is 30 μm, and the inner diameter of the rest is 10 mm;

[0062] Preferably, the outer diameter of the nozzle is 30 mm, the nozzle contains a cylindrical through hole with an inner diameter of 30 μm, the inner wall of the through hole is provided with two metal coatings as conductors, each connected to a wire, the material is metal copper or metal silver, the inner wall of the through hole is a boron nitride substrate, and the outermost end of the nozzle protrudes outside the shell. Furthermore, the nozzle part outside the shell has only one group of conductors on the inner wall, and when the droplet passes, the charge on the droplet is conducted from the conductor, so that the droplet is not charged.

[0063] Preferably, a connection notch with an inner diameter of 20 mm is provided at the inlet end of the nozzle, and is connected to the insulating tube by threaded engagement.

[0064] Preferably: the pump is a plunger pump, provided with an independent auxiliary power supply, and in multi-electric control switch mode, after the electric control switch on the pump receives the electric signal from the control circuit, it will alternately open or close the pump at fixed intervals, and will open the pump when no electric signal is received; in single electric control switch mode, after the electric control switch on the pump receives the electric signal, it will close the pump, and will open the pump when no electric signal is received.

[0065] Preferably, the magnetic field generator is provided with an independent auxiliary power supply and a magnetic field coil. After the electric control switch on the magnetic field generator receives the electrical signal transmitted by the wire, the magnetic field generator is turned on to generate a current of a set current intensity in the magnetic field coil, thereby generating a strong magnetic field.

[0066] Preferably, the auxiliary laser generator is provided with an independent auxiliary power supply. After the electronic control switch on the auxiliary laser generator receives an electrical signal, it will turn on the auxiliary laser generator to generate laser light. If no signal is received within a certain period of time (such as more than 0.1 s), the auxiliary laser generator will be turned off. The effect of not immediately turning off the auxiliary laser generator after turning off the electronic control switch can be achieved by connecting a capacitor, which is prior art and will not be described in detail.

[0067] Preferably, the outer wall of the housing is provided with a coating, which is composed of alternating layers of silicon material and molybdenum material, with a total of 40 layers. The inner wall is provided with a magnetic shielding layer, and its material is soft iron, silicon steel, permalloy or soft ferrite.

[0068] Preferably, the sensor is provided with an independent auxiliary power supply.

[0069] Preferably, the laser is a carbon dioxide laser.

[0070] Preferably, a wire is connected to the inner wall of the waste receiving pipeline for discharging the charge in the waste or fuel droplets.

[0071] Now, the schematic diagram of the working principle of the electronic control switch of the fuel pump is attached to Figure 5 , it should be noted that the following methods are merely examples and do not limit the present solution. The methods described in the present solution can also be implemented by other methods disclosed in the prior art.

[0072] As shown in Figure 5, the electronic control switch 621 is in parallel with the electronic control switches 622 and 623. The electronic control switches 622 and 623 are in series. When the electronic control switches 621 and 622 receive the electrical signals generated when the control circuit is turned on, the electronic control switch 621 disconnects the circuit, the electronic control switch 622 connects the circuit, and the electronic control switch 623 is a pulse switch, which can make the circuit turn on and off at a certain frequency, so that the fuel pump 28 turns on and off at a certain frequency, thereby alternately opening or closing the fuel pump; when the electronic control switches 621 and 622 do not receive electrical signals, the electronic control switch 621 connects the circuit, the electronic control switch 622 disconnects the circuit, and the circuit where the fuel pump is located is a closed circuit, continuously turning on the fuel pump;

[0073] In addition, alternatively, when there is only the electronic control switch 621 in the circuit where the pump is located and no electronic control switches 622 and 623, the pump will be turned off when the electronic control switch 621 receives an electrical signal, and the pump will be turned on when no electrical signal is received.

[0074] Working principle of the fuel emitter in this solution: The fuel is transported to the nozzle by a fuel pump to achieve the control circuit path. The fuel pump starts or stops under the feedback of the control circuit, forming a continuous introduction of droplets. At the same time, after the electric control switch on the magnetic field generator receives the electrical signal from the control circuit, it turns on the magnetic field generator to generate a strong magnetic field. At the same time, when the fuel is running in the nozzle, the circuit where it is located is in a conductive state. Under the action of the strong magnetic field, it is affected by the Ampere force in the same direction as the running direction of the fuel droplets (the direction of the current can be determined according to requirements), and accelerates along the nozzle wall until it is emitted.

[0075] Working principle of the EUV radiation source generating device in this solution: The fuel is transported to the nozzle by a fuel pump to achieve the circuit path. The electric control switch on the auxiliary laser generator is turned on to activate the auxiliary laser generator to emit laser light. When the fuel droplets do not reach its optical path, the sensor can receive the laser light and convert it into an electrical signal. When the fuel droplets reach its optical path, they will block the optical path, so that the sensor cannot receive the laser light or only receives part of the laser light. The sensor converts it into the corresponding electrical signal, thereby realizing the monitoring of the droplet operation. The sensor transmits the generated electrical signal to the laser in the laser emission port of the ellipsoidal mirror in real time to help it identify the flight trajectory of the fuel droplets. The laser obtains relevant data before the corresponding fuel droplets reach the plasma formation area (i.e., the excitation point), determines the timing of the excitation laser pulse through data analysis, and then realizes two consecutive precise strikes to excite extreme ultraviolet light photons. Since the flight trajectory of the fuel droplets is relatively fixed, the position where the laser strikes the tin metal is relatively fixed, and the position where the point radiation source is formed is relatively fixed. The formed point radiation source can be reflected by the ellipsoidal mirror out of the light source outlet at the top of the collector, and the EUV radiation source is prepared and collected through subsequent collection.

[0076] The collector described in the present invention is inclined towards the waste receiving pipeline side to prevent waste or unexcited fuel from blocking the laser port below the ellipsoidal mirror or affecting the reflection of EUV light by the ellipsoidal mirror, making it unable to operate normally. At the same time, the wires on the pipeline discharge the charges carried by the waste or fuel droplets.

[0077] The following further illustrates this solution through examples and in combination with the principle. Example

[0078] I. The devices used in this solution, the addition techniques of the boron nitride coating and the magnetic shielding layer are all prior arts, so the preparation methods of their respective components and the addition methods of the relevant coatings will not be described in detail.

[0079] Examples of the preparation methods of the nozzle and the wire are as follows. The following methods are only examples and do not limit this solution. The structure described in this solution can also be prepared by other methods disclosed in the prior art.

[0080] 1. On a boron nitride substrate, a square slit with a length of 40 μm and a width of 20 μm is formed by laser.

[0081] 2. Surface modification of boron nitride: -OH modification is carried out on the surface of boron nitride by means of H2O2 hydrothermal treatment, ultrasonic-assisted hydrolysis or plasma treatment, etc., to facilitate subsequent tight bonding with metallic silver through chemical reactions. In this embodiment, H2O2 hydrothermal treatment is used to carry out -OH modification on the surface of boron nitride.

[0082] 3. At a high temperature of 1000 °C, liquid silver solution is dropped into the slit, and after it fills the hole, it is rapidly cooled to form a solid silver filler.

[0083] 4. With the center of the silver filler as the center, a cylindrical slit with an inner diameter of 30 μm and a circular shell with an outer diameter of 30 mm are formed by laser; the silver filler forms two non-contact areas as conductors.

[0084] 5. The shape of the shell is reprocessed by laser and numerical control machine tools, such as preparing the card slots connected to the outer shell, the shapes of the parts combined with the wire protection tube and the insulation tube, etc.

[0085] 6. Connect the wire protection tube and the insulation tube to make them all communicate. According to the methods described in steps 2 and 3, silver is added into the wire protection tube, and at the same time, metallic silver is not added into the nozzle through hole and the insulation tube as much as possible.

[0086] 7. An etching machine is used to etch along the slits of the nozzle and the insulation tube until the wire is disconnected, the nozzle and the insulation tube are opened, and it is ensured that the exposed modified boron nitride layer generated in step 6 is etched off, at the same time, the silver in the insulation tube is completely etched off, the silver coating in the nozzle is disconnected, and the two formed conductors are electrically connected to one wire each.

[0087] 8. The silver coating on one side of the part of the nozzle protruding out of the outer shell is etched off by an etching machine, and only the silver coating on one side is left to discharge the charge carried by the fuel droplets, further avoiding the deflection of the running track of the fuel droplets after leaving the nozzle.

[0088] II. According to the structure described in the specific embodiment, each device is connected. The magnetic shielding layer on the inner wall of the outer shell is soft iron; the silver coating on the non-etched side of the part of the nozzle protruding out of the outer shell is connected to the positive electrode, and the etched side is connected to the negative electrode; the fuel pump adopts a multi-electronic control switch mode, and the opening and closing interval time is controlled to be 10 - 5 s; and a monitoring system composed of 3 groups of auxiliary laser generators and sensors is set up to obtain three-dimensional data of the flight track of the fuel droplets.

[0089] It should be noted that since the electronic control switch on the pump of the fuel emitter will turn on the pump when no electrical signal is received, in actual applications, the power supply of the pump needs to be connected after the working environment, temperature and other conditions of the EUV radiation source generating device meet the requirements.

[0090] The working principle of this embodiment is as follows:

[0091] The fuel is transported by the fuel pump to the conductor at the inlet end of the nozzle, so that the fuel droplets are simultaneously connected to the two conductors, thus realizing the circuit path. After the electronic control switch on the pump receives the electrical signal, the pump is alternately turned on or off every 10 -5 s to realize the continuous preparation of fuel droplets, 50,000 drops per second; at the same time, after the electronic control switch on the magnetic field generator receives the electrical signal, the magnetic field generator is turned on to generate a strong magnetic field; at the same time, when the fuel is running in the nozzle, the circuit where it is located is in a conductive state, and there is always a current passing through each fuel droplet. Under the action of a strong magnetic field of the same intensity, it is affected by the Ampere force in the same direction as the running direction of the fuel droplet and moves along the nozzle wall by accelerating and is emitted. In addition, when the fuel droplets are running in the nozzle, since the acceleration magnitude of each fuel droplet at any moment is the same or approximate, the running speed of the previously generated fuel droplets is always faster than that of the later generated fuel droplets, thus avoiding the fusion between droplets; at the same time, after the electronic control switch on the auxiliary laser generator receives the electrical signal, the auxiliary laser generator is turned on to emit laser. When the fuel droplet has not reached its optical path, the corresponding sensor will receive the laser and convert it into an electrical signal. When the fuel droplet reaches its optical path, it will block the optical path, so that the sensor cannot receive the laser or only receives part of the laser, thus generating a corresponding electrical signal. Multiple groups of sensors transmit the electrical signals to the laser at the laser emission port of the ellipsoidal mirror in real time through wires to help it identify the flight trajectory of the fuel droplets. The laser obtains relevant data before the fuel droplets reach the plasma formation area, determines the timing of the laser pulse excitation through data analysis, and then realizes two consecutive precise strikes to excite extreme ultraviolet light photons. Since the flight trajectory of the fuel droplets is relatively fixed, the position where the laser strikes the metallic tin is relatively fixed, so that the position where the point radiation source is formed is relatively fixed. The formed point radiation source can be reflected by the ellipsoidal mirror out of the light source outlet at the top of the collector, thus realizing the preparation and collection of the EUV radiation source.

[0092] The collector in this embodiment is inclined towards the waste receiving pipeline side to prevent waste or unexcited fuel from blocking the laser port below the ellipsoidal mirror or affecting the reflection of EUV light by the ellipsoidal mirror, so that it cannot operate normally. At the same time, the wires on the pipeline discharge the charges carried by the waste or fuel droplets.

Claims

1. A fuel emitter, characterized in that: It includes a nozzle, on the inner wall of which there are two groups of conductors axially arranged, and on the outer wall of the nozzle there are two wires symmetrically arranged, and the two wires are electrically connected to the two groups of conductors respectively; it also includes a magnetic field generator which is arranged outside the nozzle and the magnetic field direction is perpendicular to the nozzle and the wires; there is a housing arranged outside the nozzle and the magnetic field generator, and the outermost end part of the nozzle protrudes outside the housing; it also includes a fuel pump, the inlet end of the fuel pump is connected to the fuel storage tank through an insulating pipe, and the outlet end of the fuel pump is connected to the inlet of the nozzle through an insulating pipe; There is a protective pipe arranged outside the wire, and the wire and the protective pipe are arranged along the radial direction of the nozzle; There is a magnetic shielding layer on the inner wall of the housing, and its material is soft iron, silicon steel, permalloy or soft ferrite.

2. The fuel emitter according to claim 1, characterized in that: The magnetic field generator and the fuel pump are provided with electric control switches and are electrically connected to the wire.

3. An EUV radiation source generating device, characterized in that: It includes the fuel emitter as described in claim 1; it also includes a collector, a monitoring system, a laser, and a waste receiving pipeline; the collector includes a conical housing, at the upper part of the housing there is a light source outlet, at the lower part of the housing there is an ellipsoidal reflector, and at the bottom of the ellipsoidal reflector there is a laser emission port which is matched with the laser; the fuel emitter and the waste receiving pipeline are correspondingly arranged on both sides of the housing; the monitoring system includes an auxiliary laser generator and a sensor which is matched with it, and the two are correspondingly arranged on the housing, and the connection line intersects with the running path of the fuel droplets.

4. The EUV radiation source generating device according to claim 3, characterized in that: The auxiliary laser generator is provided with an electric control switch and is electrically connected to the wire of the fuel emitter.

5. The EUV radiation source generating device according to claim 3, characterized in that: The fuel is metallic tin.

6. The EUV radiation source generating device according to claim 3, wherein: The insulating pipe and the nozzle are both made of boron nitride, and the tank wall of the storage tank and the inner wall of the pump are both provided with boron nitride insulating layers.

7. The EUV radiation source generating device according to claim 3, characterized in that: The conductor is silver or copper.

8. An EUV radiation source generating device according to claim 3, characterized in that: There is a coating on the outer wall of the housing, which is composed of alternating silicon material and molybdenum material, and there is a magnetic shielding layer on the inner wall, and its material is soft iron, silicon steel, permalloy or soft ferrite.

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